Boakd drop-hammer



A. B. GARDELLA.

BOARD 'DROP HAMMER. APPLICATION FILVED NOV. 3, 1919.

1,363,4 5, Patented M128, 1920.

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ALBERT B. GARDELLA, 0F CLEVELAND, QHIO.

BOARD DROP-HAMMER.

Application filed November 3, 1919.

To all whom it may concern Be it known that I, ALBERT B. GARDELLA,

a citizen of the United States, residing at Cleveland, in the county of Guyahoga and State of Ohio, have invented certain new and useful Improvements in Board Drop- Hammers, of which the following is a speciiication.

This invention relates to an improvement in board drop hammers and more particularly to an improved means for controlling the friction rolls which engage the board to which the ram is secured and which raises and lowers the ram.

As is well known to those familiar with this type of hammer, the means for controlling the aforesaid rolls includes an actuating rod. This rod is a constant source of trouble due to its breaking very frequently from the excessive strains and vibration imposed upon it by the operation of the hammer, it therefore follows that this rod must necessarily be made very substantial and conse quently is very costly. Furthermore the frequent breakage thereof throws the corresponding hammer out of operation during the time taken to make repairs and therefore entails considerable loss to the manufacturer.

The important feature therefore of the invention is in the provision of means which eliminates the aforesaid actuating rod and thereby the atten din di'fliculti es.

The improved means hereinafter described comprises a cheap, efiicient and durable con struction which is simple in operation and which will positively remove the above mentioned troubles.

In the annexed drawings forming part of this specification and in which similar letters of reference indicate similar parts throughout the various views, Figure l is a front elevation of a hammer with my invention applied thereto, and Fig. 2 is a side elevation, certain parts being broken away for clcarness of illustration.

The invention comprises the usual base 1, vertical guides 2 and top 3 which compose the main frame work of the hammer. The top 3 supports the main actuating means for the ram which consists principally of two friction rollers 4 and 5. The roller 4 is mounted upon an eccentric bushing 6 which has made integral therewith a crank arm 7 whereby the roller may be moved toward and from the roller 5 which is placed within Specification of Letters Patent.

Patented Dec. 28, 1920.

Serial No. 335,487.

fixed bearings in the top 3 and acts as the driving roller, having power supplied to it by means of the large pulley 8 fixed to the same shaft.

The actuating means comprising the novel features of this invention has to do with the moving of the roller 6 into and out of frictional engagement with the board 9 which lies between the aforesaid roller and the roller 5 and has the ram secured to its bottom end, the ram being fixed to reciprocate vertically within suitable guides 11 formed as part of the sides 2.

Fixed to the crank arm 7 is a link 12 which has secured to its upper end one end of a lever 13, said lever being pivotally supported at its middle upon a bracket 1% which is fixed to the top 3, and the opposite end of the lever 13 has secured to it a cable 15 which has connection with a rack 16. This rack is permitted to move vertically within guides 1'? formed upon the side of the frame and meshes with the pinion 18 carried upon a shaft 19 mounted within suitable bearings 20 formed on the main frame work. Upon the shaft 19 is mounted a friction brake 21 to retard the movement of said rack and pinion as will be hereinafter described. To the lower portion of the rack is secured a cable 22 which passes between threeidler pulleys 2 1, one of said pulleys being mounted upon a lever 25 whereby any slack in said cable may be conveniently taken up. The cable passes from thence downwardly and horizontally over two pulleys 26 and thence vertically to the lower end of the link 12 where it is permanently attached.

Upon the upper portion of the rain and at that side which is nearer to the cable is fixed a projection 27 which has its end in the form of a ring thereby to encircle the vertical portion 28 0f the cable. Upon the ram between the two rollers 4 and 5 and cause the hammer to fall by gravitv. by pressure upon the foot pedal 30 which opei'ztte's through a rod 31, releasing the mechanism indicated generally at 32 and which is of a type common to all presses. As the hammer falls it is desirable to gradually check the speed of it as it approaches theextreme lower limit and this is accomplished by a push rod tl being engaged by a cam face 31 upon the ram 10, said push rod being guided within a bearing 43 and operating upon a bell crank 33 pivoted to the main frame and having its other arm encircling the cable to engage an abutment 34:, thereby to cause the cable to move in an opposite direction to that hereinbefore described and through the rocker arm 13 and link '12 causes the crank arm 7 to move in a direction to throw the rollers 4 and 5 into frictional engagement with the board, this then raises the ram to its upward position, where it is held as before described. The friction brake 21 hereinbefore referred to tends to prevent any extreme or rapid motion of the moving parts and prevents any undue vibration thereof.

As this apparatus is confined to a means for automatically controlling the frictional rollers which engage the board I have not deemed it necessary to describe in detail the other parts of the hammer, all of which are of a standard construction and are well known to those familiar with the art and while I have shown in the drawings and described this specific form of apparatus I do not wish to'limit myself in the detailed construction of the same further than is required by the state of the art or that which comes within the scope of the appended claims.

I claim:

1. The combination with the board of drop hammer, and rolls to engage the board, of means to operate one of the rolls to grip and release the board, said means including a cable having an abutment thereon, and a projection carried by the ram of the hammer and engageable with the abutment when the hammer is lifted to shift the cable and actuate said. means to release the rolls from the board.

2. The combination with the board of a drop hammer and rolls to engage the board and lift the hammer, of means to operate one of the rolls to grip and release the board, said means including a cable, means actuated by the hammer at the limit of its lift to shift the cable in one direction and re lease the roll from the board, and means actuated by the hammer at the limit of its drop to shift the cable in the other direction and engage the roll with the board 8. The combintaion with the board of a drop hammer and rolls to engage the board, of means to operate one of the rolls to grip and release the board, said means including a cable, and devices automatically actuated by the lift and drop of the hammer to shift the cable in opposite directions at the limit of movement of the hammer in either di rection respectively.

The combination with the board of a drop hammer and rolls to engage the board, of means to operate one of the rolls to grip and release the board, said means including a cable, and devices automatically actuated by the lift and drop of the hammer to shift the cable in opposite directions at the limit of movement of the hammer in either direction respectively and brake mechanism actuated by shift of the cable to retard the movement thereof.

5. The combination with the board of a drop hammer and rolls to engage the board, of means to operate one of the rolls to grip and release the board, said means including a cable, and devices automatically actuated by the lif and drop of the hammer to shift the cable in opposite directions at the limit of movement of the hammer in either direction respectively, and brake mechanism actuated by shift of the cable to retard the movement thereof, said brake mechanism comprising a brake drum, a shaft carrying the drum, a pinion on the shaft, and a sliding rack connected to the cable and engaging the pinion.

6. The combination with the board of drop hammer and rolls to engage the board, of means to operate one of the rolls to grip and release the board, said means including a lever operatively connected to one of the rolls to shift it toward and from the other, a cable connec ed at its opposite ends to the lever and extending beside the hammer, means carried by the hammer to engage the cable at the limit of the lift of the hammer and shift the cable and thereby the lever in one direction, to release the board, and means actuated by the hammer at the limit of its drop to engage the cable and shift it and the lever in the opposite direction, to grip the board. j

7. The combination with the board of a drop hammer, and rolls to engage the board, of means to operate one of the rolls to grip and release the board, said means including a cable having an abutment thereon, and a projection carried by the ram of the hammer and engageable with the abutment whenthe hammer is lifted to shift the cable and actuate said means to release the rolls from the board and means to take up slack in the cable.

In testimony whereof, I do aflix my signature in presence of two witnesses.

ALBERT B. GARDELLA. Witnesses:

EUGENE A. CANNING, JOHN A. BOMMHARDT. 

